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00925njm 22002777a 4500 dc Dittrich, Bianca author Martín Benito, Mercedes author Steinhaus, Sebastian author 2014 So far spin foam models are hardly understood beyond a few of their basic building blocks. To make progress on this question, we define analogue spin foam models, so-called “spin nets,” for quantum groups SU(2)_k and examine their effective continuum dynamics via tensor network renormalization. In the refinement limit of this coarse-graining procedure, we find a vast nontrivial fixed-point structure beyond the degenerate and the BF phase. In comparison to previous work, we use fixed-point intertwiners, inspired by Reisenberger’s construction principle [M. P. Reisenberger, J. Math. Phys. (N.Y.) 40, 2046 (1999)] and the recent work [B. Dittrich and W. Kaminski, arXiv:1311.1798], as the initial parametrization. In this new parametrization fine-tuning is not required in order to flow to these new fixed points. Encouragingly, each fixed point has an associated extended phase, which allows for the study of phase transitions in the future. Finally we also present an interpretation of spin nets in terms of melonic spin foams. The coarse-graining flow of spin nets can thus be interpreted as describing the effective coupling between two spin foam vertices or space time atoms. Dittrich, Bianca, et al. «Quantum Group Spin Nets: Refinement Limit and Relation to Spin Foams». Physical Review D, vol. 90, n.o 2, julio de 2014, p. 024058. https://doi.org/10.1103/PhysRevD.90.024058. 2470-0010 10.1103/physrevd.90.024058 https://hdl.handle.net/20.500.14352/99271 2470-0029 https://doi.org/10.1103/physrevd.90.024058 https://arxiv.org/abs/1312.0905 Quantum group spin nets: refinement limit and relation to spin foams